(1) Field of the Invention
The present invention relates generally to release mechanisms, and more particularly to a water-impact release mechanism used to couple a deceleration device, e.g., a parachute, to the aft end of an air-deployed device, e.g., a torpedo.
(2) Description of the Prior Art
In some Navy applications, torpedoes having air stabilizing devices (e.g., a parachute) are launched from an aerial platform (e.g., helicopter, airplane, etc.). The use of an air stabilizing device reduces the velocity upon water impact in order to prevent damage to the torpedo's structure or control systems. The air stabilizing device is generally coupled to the aft end of the torpedo by means of a release mechanism that causes the air stabilizing device to separate from the torpedo when it strikes the water. More specifically, a tail nut (i.e., similar to a hitching ball) generally extends from the aft end of the torpedo for cooperation with the release mechanism.
A variety of release mechanisms have been designed and used by the Navy. One type of release mechanism is disclosed in U.S. Pat. No. 2,880,687 where the aft end of the torpedo employs concentric sleeves to position and press a plurality of balls into engagement with a shaped plug mounted on the air stabilizing device. At impact with the water, deceleration of the torpedo brings about inertial movement of one of the sleeves such that the balls are allowed to disengage from the shaped plug. However, the inertial force is opposite that of the friction force generated by the drag force of the air stabilizing device. Accordingly, if the inertial force does not overcome the drag force sufficiently, the release mechanism can fail causing the torpedo to drag the air stabilizing device into the water.